Duck Soup - a food for convalesent British ferrets

Most ferret-keepers have some equivalent of "Duck Soup" - a high-fat, high-protein soft food to be given to ferrets who are ill or recovering. The only thing these recipes have in common is that they contain no duck...
 

All the recipes I was able to find online were American, and contained brand-names I'd never heard of, units I couldn't deal with (I can never remember how much is "a cup"), and occasionally contained things like sugary caffeinated drinks, which didn't seem a good idea for a species prone to diabetes and insulinomas. Not to mention all the recipes with homoeopathic tablets in them!

In the interests of information, here's a British recipe, with none of the above problems:

Ingredients

About 250g of dried ferret kibble (mine eat the James Wellbeloved stuff)

1 pack of chicken livers - about 300-400g, I guess

2 tablespoons butter

2 tablespoons cheap cod-liver-oil (the cheapest you can find - it'll be 50% sunflower oil, and really pungent)

Method

1. Soak the kibble in an equal volume of water, until it is completely mushy - about 6 hours for cold water, at least 2 hours for hot water.

2. Melt the butter in a pan, and gently fry the chicken livers until lightly brown on the outside, but still pink inside.

3. Put everything - kibble, butter, livers, cod-liver-oil - in a food processor, and blend until smooth. It will look like chocolate mousse.

4. Feed to poorly ferret.With a syringe if necessary.

This will only keep for a couple of days, even in the fridge, so I usually freeze it in ice-cube trays, and then defrost a few lumps (about 5-10 seconds per lump in the microwave) as and when needed.

Despite multiple terminal conditions, Wellesley lived a happy six months or so on this diet, and I doubt he'd have lasted so long otherwise. I'm currently feeding ð on a pot of duck soup (made for Wellesley) I found in the bottom of the freezer, since he could do with putting on a bit of weight. He seems to like it.

Wellesley, enjoying life